• Agrochemical news magazine
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• v.15 no.5 s.122
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• pp.76-79
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• 1994

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.214-218
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• 1996

배나무잎 이상반점증상의 보독여부를 신속정확하게 검정할 수 있는 목본 지표식물을 선발하기 위해 시험을 수행하였다. 신고x조생적 등 5개 교배조합 102개체를 공시해서 1차로 10개체를 선발하였다. 1차로 선발된 개체중에서 전형적인 이상반점증상이 조기에 잘 나타나고 이상반점증상과 유사한 검은무늬병에 저항성인 신고$\times$조생적 86-2-2 계통을 최종선발하였다. 선발된 지표식물을 사용하여 농가포장에서 이상반점 증상의 보독여부를 실증시험한 결과 보독유무의 조기판별이 가능하였다. 이상의 결과에서 최종 선발된 신고$\times$조생적 86-2-2계통을 PS-95로 명명하고자 한다.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.73-82
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• 2000

Two Psyllidae species of Cacopsylla pyricola (Foerster) and C. pyrisuga (Foerster)damaging pear trees have been reported in Korea. However, their ecological characteristics and damagepatterns have not been evaluated yet. To establish basic control measures of C. pyricola, field phenology,overwintering ecology, seasonal fluctuation and temperature-dependent development of C. pyricola wereexamined. C. pyricola overwintered under the bark scale of pear trees as winter form adults and theymoved to fruiting twigs from mid-February. Honeydew produced by C. pyricola nymphs and adults asthey feed caused serious black sooty mold on leaves and fruits. The seasonal occurrence of C. pyricolawas different every year. In 1993, characterized by cold temperature and heavy precipitation, C. pyricolapopulation was maintained highly during growing season. However, the population was decreased rapidlyfrom early July in 1994, year of hot and dry weather condition. In 1995, year of average temperature, thedensity of C. pyricola population was decreased during hot months of July and August, and rebuilt up inSeptember and October. The development periods of C. pyricola eggs were 13.33 days at 15"C, 9.32 daysat 20$^{\circ}$C, 7.82 days at 25"C, 6.60 days at 30$^{\circ}$C, and 7.75 days at 35$^{\circ}$C. The development periods ofnymphs were 33.75 days at 15OC, 23.77 days at 20$^{\circ}$C, 15.21 days at 25"C, and 17.40 days at 30$^{\circ}$C. Theirdevelopment periods and mortalities were increased in higher temperatures. The parameters of nonlineardevelopment model, Weibull and linear development models of Cacopsylla pyricola were estimated.models of Cacopsylla pyricola were estimated.

• Landscaping Tree
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• s.104
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• pp.26-27
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• 2008

녹병은 향나무뿐만 아니라 산당화, 꽃사과, 산사나무, 명자나무 등 조경수에도 많이 발생되며, 조경수목으로서의 미관적 가치를 크게 떨어뜨리고 잎 뒷면에 발생되는 녹포자퇴는 사람들에게 혐오감을 준다. 또한 배나무, 사과나무 등의 과일의 상품성과 생산량을 크게 저하시켜 농가에 큰 피해를 준다. 녹병은 일반적으로 농가에서는 붉은별무늬병으로 잘 알려져 있는 병해이다.

• Research in Plant Disease
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• v.8 no.4
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• pp.254-257
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• 2002

It was conducted to investigate an effective control measure of the black necrotic leaf spot disease on pear, The disease commonly occurred in major cultivation areas of Korea revealed 5.6 ％ infection rate on the widely growing cultivar Niikata. The disease substantially reduced yield and quality of pear fruits, however, it has never been controlled by chemicals. Renewal of the pear trees to resistant cultivar was found to be the most effective to control the disease. As a result, the disease did not developed for 2 years on the diseased Niikata that was top-grafted with resistant cultivars Soowhang and Whasan. lop-grafting with resistant cultivars was recommended far the pear trees showing over 80％ infection rate and lower than 70% fruit yield compare to standard production.

• Korean journal of applied entomology
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• v.17 no.3 s.36
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• pp.139-142
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• 1978

Activities of several hydrolytic enzymes in the rusted pear loaves were estimated. Tested enzymes were cellulase (Cx), invertase $\beta-amylase$, pectinase (pectinmethylesterase and polygalacturonase), and phosphatase. Enzyme activities represented by pH value-enzyme activitycurve. Activities of Cx. invertase. and $\beta-amylase$ were higher in the healthy part than those in the near-lesion and lesion parts. and showed the maximal activities around pH 7.0. On the other hand, activities of pectinase and phosphatase were higher in the lesion and near-lesion parts than in the healthy part. Pectinmethylesterase activities in the healthy and diseased parts were different with different curve-pattern as the pH of treating solution changed.

• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.557-570
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• 2016

Growth of 6-year old 'Niitaka' pear (Pyrus pyrifolia Nakai) trees and control of insect and disease occurrences were compared between fermented soybean extracts and rain-shelter system for two years. Foliar application of fermented soybean extracts was applied at 6 times as a pre-experiment in the open-field in 2013, with a rain-shelter system in 2014. Fermented soybean extract treatment increased foliar concentrations of approximately 0.46% T-N, 0.17% K, 0.19% Ca, and 0.06% Mg in 2013 compared to the control, with similar macro-nutrients between the control and soybean extract treatment observed in 2014. Rain-shelter system increased foliar concentrations of T-N, Ca, and Mg compared to the open-field. There were no significantly different between the control and soybean extract treatment for number of leaves per fruit, leaf dry weight, phytotoxicity, and completed shoot growth on August during the two years. Rain-shelter system increased leaf dry weight and did not affect phytotoxicity in the leaves. Fruit quality parameters were mostly similar to control and soybean extract treatment for two years, with higher fruit firmness observed for soybean extract treatment. Rain-shelter system advanced 4 days of harvest dates, and increased approximately 7.0 ton fruit yield per ha, 20 g mean fruit weight, and fruit soluble solid contents compared to open-field in 2014. Soybean extract treatment little suppressed occurrence of disease and insect on the leaves and fruits in both years. Rain-shelter system increased occurrence of Venturia nashicola on the leaves and to 63.8% of Gymnosporangium asiaticum on the fruits in 2014. Strong winds and storms in May elevated relative humidity in the rain-shelter system and caused high infection of the disease occurrence, requiring for an additional green control method. Soybean extract treatment little affected tree growth and would have initiated for a long-term study to evaluate tree physiological characteristics. Rain-shelter system improved fruit productivity and advanced harvest dates, which could have been more effective facility at a Thanks Giving Day between middle and end of September.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.72-81
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• 2016

Feeding behaviors of the pear psylla, Cacopsylla pyricola, and their changing feeding behaviors were recorded and analyzed with an electrical penetration graph (EPG) analysis against 5 insecticides. And their mortality against insecticides were carried out in the laboratory. General feeding behavior patterns of C. pyricola were changed by insecticide treatments. Especially, the type and frequency of waveforms differently occurred depending on a sort of insecticides treated. Total duration of transition to waveform PE1 and phloem ingestion (waveform PE2) were significantly different between treatment and non-treatment of insecticides. When 5 different insecticides were treated on pear leaves, difference of feeding patterns were recorded. In case of treatment of benfuracarb, total duration of non-probes (waveform Np) was appeared higher than any other insecticide. However, when flonicamid and deltamethrin were treatment, total duration of stylet penetration (waveform PA) and xylem ingestion (waveform PG) were appeared higher than other insecticide, respectively. As results feeding behaviour of C. pyricola after treated insecticides with time-based consumed rate of C. pyricola, the rate of non-probe (waveform Np) was longer than start penetration (waveform PA), penetration and ingestion in parenchyma cells (waveform PC1+PC2), ingestion at phloem (waveform PD+PE1+PE2) and xylem (waveform PG). As result of direct spray treatment to C. pyricola, mortality of C. pyricola against imidacloprid was higher than any other insecticide on 24 hours after treatment. However, all of insecticides showed 100% mortality of after 48 hours. On the other hand, when 5 insecticides sprayed on the pear leaves and then C. pyricola located on the treated leaves, benfuracarb showed the most toxicity against C. pyricola among insecticides. These result was consistent with the EPG results that showed relatively longer total duration time of waveform Np (non-probes) by benfuracarb treatment.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.31-40
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• 2001

Host plants or Ectinohoplia rufipes (Motschulsky) (En) were investigated in golf courses and laboratory. E. rufipes adults fed on 61 plant species of 27 families out of 101 plant species of 41 families supplied in laboratory. In addition, twenty-seven plant species in 8 families were observed to be fed on from golf courses. Thus, total number of host plants of E. rufipes were 84 species in 29 families. E. rufipes adults preferred Japanese green alder (Alnus firma) , cherry apple (Malus sieholdii), cherry (Prunus serrulata var. spontanea) and sweet oliver (Osmantus asiaticus) in golf courses . The preference of E. rufipes adults with A. firma , P. serrulata vu. spontanea and O. asiaticus was bioassayed in laboratory. E. rufies adults preferred A. firma consuming 58.1% to O. asiaticus and p. serrulata vats. spontanea. The most number of E. rufipes adults was attracted to damaged leaf of A. firma by E. rufipes representing 45.3clo and followed by artificial damaged leaf representing 26.5% , untried feeding leaf representing 12.9% and undamaged leaf representing 4.0%. More E. rufipes adults were attracted to damaged leaf of A. firma by 67.5% than artificially damaged leaf by 30.5% or undamaged leaf treated with feces of E. rufipes by 2%.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.1-7
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• 1988

Out of 24 isolates of Alternaria collected from pear leaves, only 7 isolates from cv. Nijiseiki leaves were specifically pathogenic to susceptible pear cultivar(Nijiseiki). Other isolates from cv. Chojuro, Oksankichi and Sinko did not show any pathogenicity to pear leaves. Pathogenic isolates of Alternaria kikuchiana produced host-specific toxin (AK-toxin) in liquid culture which caused veinal necrosis only on susceptible pear leaves, while nonpathogenic isolates did not produce this toxin. Varietal susceptibility among pear cultivars to the pathogen was investigated by evaluating HST (AK-toxin) sensitivity of pear leaves, as a substitute for spore inoculation. AK-toxin which the fungus produces was toxic to pear cultivars susceptible to the pathogen such as Isipsegi and Sinsu, but was harmless to resistant pear cultivars such as Chojuro, Oksankichi, Niitaka etc. Changes in disease susceptibility and toxin sensitivity of pear leaves with aging was investigated. Disease susceptibility and toxin sensitivity in cv. Sinsu leaves appeared to vary with leaf aging; the young leaves were visibly susceptible, but older leaves (more than 2 week old leaves) became resistant.